Last month, Russia was accused of bombing a grain cargo ship just outside of Ukrainian territorial waters in the strategic Black Sea.
That attack marked the first time a missile struck a civilian vessel transporting grains at sea since the start of Moscow's invasion of Ukraine in February 2022, and was decried by the United Nations.
This week, Russia has carried out three such attacks around Ukraine's southern Odesa port region, all on foreign-flagged civilian container ships, damaging infrastructure and causing multiple casualties.
Russia has struck the port repeatedly during the course of the war, but how do laws around armed conflict differ at sea compared to on land, and what are the repercussions when it comes to attacking civilians not originating from the country under attack?
Russia strikes three ships
On Sunday, a Russian missile damaged a Saint Kitts and Nevis-flagged vessel, Paresa, loaded with 6,000 tonnes of corn in the port of Pivdennyi, Ukraine's Restoration Ministry said.
Its 15-member crew of Syrian and Egyptian nationals all escaped injury.
Then on Monday Russia launched a missile on a Palau-flagged grain ship, Optima, hours after it arrived in Odesa. Regional governor Oleh Kiper said the attack killed a Ukrainian port worker and injured five other men on board who were foreign nationals.
Ukraine's foreign minister said two ships had been damaged in the Black Sea grain-export hub in two days, calling for international action to ensure freedom of navigation and global food security.
In the third attack on Wednesday, Russia launched a ballistic missile on the port of Chornomorsk, hitting infrastructure and the Panamanian-flagged container ship Shui Spirit.
It was the largest of the three attacks, killing eight people and injuring nine others. All of the wounded were Ukrainian nationals, Mr Kiper said, but the background of those killed was not clear.
Russia's defence ministry did not provide immediate comment and it typically has not commented on more than 20 such strikes that have taken place in the Black Sea over the past month. Moscow has repeatedly denied it attacks civilian targets.
The significance of Ukraine's grain exports
Ukraine is a major global grain exporter that has had to battle Russia in the Black Sea to revive its exports through its seaports since the 2022 invasion imposed a de facto blockade.
The exports were revived from the three ports of greater Odesa later in 2022 — albeit with smaller volumes — under the Black Sea Grain Initiative mediated by the United Nations and Türkiye, allowing for ships to travel on specific routes in the grain corridor without being attacked.
That deal led to 32.8 million tonnes of food being shipped out from Ukraine to the Asia Pacific, Europe, and Africa over a year and feeding approximately 150 million people, with more than half going to developing nations.
Russia withdrew from the pact last July.
Up until it was in effect, Ukraine was the world's seventh-largest producer of wheat. It also made up 15 per cent of the global corn market, 13 per cent of the barley market and more than 50 per cent of the sunflower oil market, according to European Union estimates.
From 2016 to 2021, some poorer Asian and African countries received 92 per cent of Ukraine's wheat.
In August 2023, Ukraine established its own shipping corridor — without Russia's blessing — after using naval drones and long-range weapons to strike back at Russia's Black Sea Fleet and push its vessels away from the west of the sea.
Vessels have since been using an alternative route, hugging Ukraine's south-western Black Sea coast through Romanian waters and on to Türkiye.
With the pace of exports from Ukraine's Black Sea ports slowing, more grain shipments are leaving from ports located along the Romanian border on the Danube River, however, these are far less capable in terms of the volume of cargo they can move.
The EU says Russia's attacks on Ukrainian grain vessels have aggravated the global food crisis and led to major food insecurity for millions of people by depleting supply levels and further driving up prices.
What is the law of armed conflict at sea?
After the first grain vessel attack in September in which Ukraine accused Russia of using strategic bombers, the UN said any targeting of civilian vessels and port infrastructure "are prohibited under international law and must stop".
"Ensuring the safety and sustainability of agricultural exports passing through the Black Sea remains critical for supporting global food security and keeping global prices under control," UN spokesperson Stephane Dujarric said at the time.
The United States also condemned the attack, with its ambassador to Ukraine, Bridget Brink, saying: "This escalatory attack is a blatant violation of international law that threatens global food security."
Russia's ongoing land invasion of Ukraine is widely considered to have broken international laws of war in various contexts, including by organisations like the UN, Amnesty International, Human Rights Watch, and foreign policy think tanks.
Naval warfare has also run in parallel to the fighting on land, but owing to the Black Sea Grain Initiative from July 2022 to July 2023, attacks were restricted to warships and excluded merchant shipping.
By pulling out of the agreement, Russia effectively deems all containers entering or leaving Ukraine from the Black Sea to be carrying military cargo, and can choose to strike regardless of their flag, the nationalities of those manning them, and whether or not they act provocatively.
According to the Law of Armed Conflict (LOAC) at Sea, a neutral civilian ship can only legally be intercepted if it is carrying military "contraband" for the enemy country, fails to comply with calls to be stopped and searched, or enters the waterway during a formally imposed blockade,
[DW]Human Rights at Sea says Moscow's attempts to prevent access to Ukrainian ports without formal interdiction of contraband vessels or a blockade are unlawful and breach human rights protections.
"What Russia cannot do, and what it appears to be suggesting it will do, is simply regard all merchant shipping in the Black Sea as legitimate targets for attack without first establishing their engagement in the transport of contraband and/or non-neutral service," David Hammond, CEO of the UN-accredited NGO said.
"Russian maritime forces must therefore stop, visit and search vessels before either seizing them as a prize or destroying them if the decision is to do so (after removing their crews to a place of safety) if they are found to be carrying contraband, for example."
Currently, there is no evidence indicating any of the Ukrainian grain vessels struck by Russia this week or through the past month were carrying contraband destined for Kyiv, failed to follow stop and search orders, or were acting on behalf of Ukraine or under its military control.
Russia also does not have the right to exercise any control over ships sailing the territorial waters of Bulgaria and Romania — both members of the West-backed security alliance NATO — in the Black Sea.
What are the consequences of attacks on civilians?
It is forbidden to carry out any direct attacks against civilians under international humanitarian law.
It is also prohibited to launch an attack that may be expected to cause incidental loss of civilian life, injury to civilians, or damage to civilian objects.
This includes attacks on neutral merchant ships, which are privately owned ships used for the transport of goods and civilian persons. Crews on board merchant ships are classed as civilians, if they are not contributing to military action.
Serious violations of international humanitarian law constitute war crimes and individuals can be held individually criminally responsible.
The International Criminal Court prosecutes those accused of war crimes, crimes against humanity and genocide. But it can only hear a case if the country where the offence was committed is a party to the Rome Statute or the perpetrator's country of origin is a party to the Rome Statute.
While Ukraine is not a party to the Rome Statute, it has twice exercised its prerogatives to accept the Court's jurisdiction over alleged crimes under the Rome Statute occurring on its territory.
ABC/Reuters
